Influenza virus is a Category C biodefense pathogen of global public health concern because it causes 3-5 million cases of severe illness every year, and because of the potential for the emergence of new, highly pathogenic strains that could cause pandemic disease. To date, there have been only two successfully-exploited influenza drug targets and only four approved drugs. The M2 H+ ion channel has been shown to be necessary for viral infectivity, and suppression of its activity is a well validated anti-viral strategy. The compounds amantadine and rimantadine inhibit M2 and have been used as influenza therapeutics for the past 40 years. However, many currently circulating influenza strains now exhibit resistance to them. New drugs that inhibit M2 via novel mechanisms of interaction therefore have significant potential as influenza therapeutics. However, conventional methods for studying the activity of ion channels are poorly suited to high-throughput screening techniques for identifying new inhibitors. Until now, this has largely precluded the development of new classes of M2 inhibitors. Integral Molecular specializes in developing novel strategies for manipulating and studying integral membrane proteins, including ion channels. We have developed a novel technology for monitoring the activity of M2 that we have shown to be well-suited to high-throughput screening (HTS) applications. Having successfully developed a suitable HTS assay for M2 screening, the current application proposes to use it to identify and develop novel M2 inhibitors. PUBLIC HEALTH RELEVANCE: The product that will result from this SBIR is a novel small molecule inhibitor of influenza. The inhibitors developed in this proposal will target a validated influenza molecular target, M2, and overcome the major obstacles faced by the adamantane drugs because compounds will be screened for potency against a number of M2 variants to maximize the chances of developing a broad-spectrum influenza inhibitor. M2 is critical to the influenza life-cycle, suggesting there is substantial therapeutic potential for next-generation inhibitors of M2 activity.